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971.
Challenges to traditional public sector approaches to urban government have had an impact on various aspects of governance and management, including political arrangements, decision making processes, ways of ensuring accountability, the allocation of roles and responsibilities between public sector agencies and other potential service providers and between different levels of government, and the mobilisation and allocation of financial resources for urban development. These are discussed, drawing in particular on recent research on urban poverty and governance in ten cities in the South. The changing approaches to urban government and management have been accompanied by attempts to define criteria by which urban governance arrangements and performance can be assessed, which are summarised and critically evaluated. Finally, the potential value of a particular set of tools (GIS) for emerging approaches to urban governance is assessed. Their potential for improving the information available to all governance actors is recognised. However, because of their cost and technological and managerial demands, as well as the limited effectiveness of spatial planning and inequalities in access to information, plans for their use must be financially, institutionally and politically realistic.  相似文献   
972.
Abstract: Since the late 1980s the Brazilian population in Japan has steadily increased, despite the long‐term recession in the late 1990s. In this paper we will examine the mechanism of the constant increase of Brazilians in Japan, focusing on the institutional context of their incorporation into the Japanese labor market. On the demand side, Brazilians solved an acute labor shortage in the economic boom period, but long‐term recession and casualization of the labor market made them compete with other peripheral workers such as Japanese women and the aged. Thus Brazilians have been marginalized within the secondary labor market since the late 1990s. On the supply side, recruiting agencies and labor contractors established a “just‐in‐time” labor delivery system, which enabled “flexible staffing” in a highly fluctuating labor market. As a result, demand and supply for Brazilian workers is still on the increase. Working in Japan is getting less attractive for Japanese Brazilians but is more of a viable option for them, driving further migration from Brazil to Japan.  相似文献   
973.
论述了气动系统中空气压缩机变速运行的技术。导出了管网工作压力及工作流量与电机转速之间的控制数学模型。利用电机无功功率信号控制调频调压逆变器供电的感应电机的磁通,使其保持恒定、則气路系统在宽流量变化范围內能实现压力自动调节及电机节能。  相似文献   
974.
制度与经济发展有着内在的联系,是经济发展的重要变量.中国农业发展的曲折历程,实质上是中国农业制度选择的曲折.制度对农业发展有着决定性的影响作用,以制度建设为中心就成为解决中国三农问题的必然选择.  相似文献   
975.
本文推广了文[1]的结果,给出了正方程组存在正解的某些新条件.  相似文献   
976.
A marginal and sequential maximum likelihood estimation method is described which can be used instead of full information maximum likelihood estimation if the latter method is unfeasible. It is shown that the sequential procedure yields strongly consistent and asymptotically normal estimates under relatively general regularity conditions. It is shown that the covariance matrix of the sequential ML estimator does not coincide with the inverse of the Fisher information matrix. Hence, the corrected covariance matrix is derived. The application of the sequential procedure to the multivariate probit model with dichotomous, ordered categorical, single-sided censored and double-sided censored endogenous variables is included. This research was partially supported by a dissertation grant of theStudienstiftung des Deutschen Volkes. Comments and suggestions on earlier drafts by Gerhard Arminger, Giorgio Calzolari, Bernd Kortzen and an anonymous referee are gratefully acknowledged.  相似文献   
977.
多普勒散布及多径展宽等时频特性会使高频数据通信系的的误码率产生一个不可减小的误码率,根据短波授时自动收测系统和多次包络法测多普勒展宽和多径展宽的测量结果,本文重点讨论二者的时频特性及其对数据通信系统性能的影响。  相似文献   
978.
电子系统电磁兼容预测模型研究   总被引:3,自引:0,他引:3  
建立了电子系统电磁兼容性预测分析必需的数学模型,包括干扰预测方程、天线、接收机和发射机的模型模拟,以及传输函数模型等。利用折线拟合模拟天线方向图,分析了干扰模型落入接收机模型的7种位五关系和发村机的辐射模式,传输通过考虑了自由空间,准平滑地形,不规则地形等。  相似文献   
979.
This paper explores two themes that had a significant place in Durkheim's Division of Labor:the idea that people's needs and wants vary across epoches and cultures, and the conception of societies as systems. The first leads to a rejection of efficiency as the primary driving force behind advances in the division of labor. Considering power in addition to efficiency, but also the complex conditions of trust and meaning, leads into questions of interdependence and systems analysis.  相似文献   
980.
讨论了用柱布朗运动过程驱动,在Banach空间中取值,用随机发展方程描述的随机分布参数系统的最优控制问题。用文献[1]中的方法得到了状态过程的轨道变分的表达式和最优控制的必要条件与充分条件。  相似文献   
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